Before I begin let me just say that I'm white and my skin tone is very light (not super pale but not tan either) and sensitive. I started shaving my head about 6 months ago on every two to three days. In the beginning of shaving I did get red bumps that felt like acne, however those bumps are gone now....but I now have an issue with small flat red dots. A day or two after shaving I get small flat red dots on the back part of the crown of the head. The red dots look like acne but they're not acne, nor are they bumps. These red flat dots do not appear anywhere else on my head or face...just the back of the crown. I used Proactiv thinking that might help but it did not help. I just started using HeadBlade's Head Shed and Clear Head products. For a Razor I either use a Edwin Jagger DE89Lbl Lined Detail Chrome Plated Double Edge Safety Razor (with Derby blades) or Gillette Fusion Power Men's Razor or a HeadBlade Moto. Shaving creams are Gillette Fusion, Bee Bald, CREMO, and Head Slick. Yesterday I ordered Thayers Alcohol-free Witch Hazel with Aloe Vera. Any advice on products or techniques will be greatly appreciated.
Can you post a picture? I'm willing to bet that you have a case of "stork bite" which is the reddish pigmentation at the back of the head that many people have. It's not a big deal, but if you do have stork bite, and if it's a big issue for you, you may need to see a dermatologist for some bleaching cream.